As far as the keying went, I saw a few problems. In several shots, the subject had a very hard "cut out" edge that was not natural looking. In others, the edge was messy and pixelated - looked like you were having a hard time with a dv master. There was no light wrap which would have helped integrate the subject into the background in some of the shots. Also, I'm a little confused - were you only doing the keying or were you also generating the digital sets?
I think it's a good start - and if the master is dv I think it's an excellent start. I'd just look at tweaking your keys a little to really make them sing. What app are you doing this in?
Finally - for some reason "Carmina Burana" has suddenly become popular as a background track for reels. I'd consider something else.